Window alarm



Oct. 16, 1951 J, W- BROQKS 2,571,534

WINDOW ALARM Filed Jan. 20, 1950 v K 30 z 0 if I7 27 ATTORNEYS Patented Oct. 16, 1951 UNITED STATES PATENT OFFICE WINDOW ALARM James W. Brooks, Knoxville, Tenn.

Application January 20, 1950, Serial No. 139,569

(Cl. 20D-54) 3 Claims. v l

This invention relates to a window alarm, and more particularly to an alarm device for attachment to a window frame having a protective window guard for indicating, by an audible or visible alarm, that the window guard is being tampered with It is an object of this invention to provide a Window guard of the kind to be more particularly described hereinafter having a window guard frame to be supported on the window frame by an alarm switch, the switch to be closed for energizing an alarm circuit upon displacement of the guard frame in any direction by an unauthorized person.

Another object of this invention is to provide a window guard of this kind having a switch with a movable contact to be engaged with one of a plurality of xed contacts for closing an alarm circuit upon movement of a guard frame suspended from the movable contact member.

Still another object of this invention is to provide an electric switch for an alarm circuit of this kind, the electric switch being adapted to be closed upon movement of the movable contact member in a vertical or horizontal direction.

A further object of this invention is to provide a burglar alarm of this kind which is compact in nature, simple in structure, and adapted to be manufactured and distributed at a low price for use in places where a plurality of such circuits is desired to be used.

With the above and other objects in View, my invention consists in the arrangement, combination and details of construction disclosed in the drawings and specification, and then more particularly pointed out in the appended claims,

In the drawings:

Figure 1 is a front elevation of the window having a -window alarm of this kind, the drawing showing the alarm circuit in diagrammatic form;

Figure 2 is a front elevation, partly broken away, of the switch member used in the alarm;

Figure 3 is a. vertical, transverse section taken on the line 3-3 of Figure 2;

Figure 4 is a vertical, longitudinal section taken on the line 4-4 of Figure 3;

Figure 5 is a top plan view, partly broken away, of the switch elements broken away from the alarm circuit and window guard frame; Figure 5 being substantially a top plan view of Figure 2.

Referring to the drawings, the numeral I0 designates generally a window frame, or frame about any 4other opening, on which a Window alarm II, constructed according to an embodiment of my invention, may be employed.

The alarm II comprises a window-closing guard frame I2 to be supported on an electric switch I4 which is connected in an alarm circuit I5 including an audible alarm member, such as a bell I6. While an audible alarm, as the bell I 6, is shown in the'drawings, it is to be understood that any other type of alarm device, such as an alarm light or the like, may be used,

The guard frame I2 comprises a pair of transversely spaced apart, vertically extending frame members I'I and I8 which are connected together by a plurality of transverse frame members or bars I9. The vertically extending side frame members I1 and I8 are adapted to overlie the side portions or members of the window frame l0, while the transversely extending frame members I9 are adapted to extend across the opening which is to be covered, or protected, by the window guard frame I2. The uppermost of the transversely extending guard frame members, the member 20 as noted in the drawings, is adapted to be extended at its opposite ends outwardly beyond the side frame members II and I3, as clearly noted in Figure 1 of the drawings.

An alarm switch I4 is adapted to be fixedly Secured to the window frame I0 at the opposite upper corners thereof, as clearly noted in Figure 1 of the drawings, the guard frame I2 to be suspended from the switches I4 in the manner to be more particularly described hereinafter.

Each of the switches I4 is formed with a body or casing 2l formed of wood, plastic, or other suitable insulated material formed to ani suitable shape, the casing 2l being adapted to be secured by any suitable fastening means, not shown in the drawings, to the surface of the window frame I0. Each of the switches I4 is formed in the same manner, and therefore it is submitted that a detailed description of one of the switches I4 may be suitably applied to the. other of the switchesV I4.

The insulated casing 2| is provided with a vertically extending bore 22 opening through the upper and lower ends thereof, as clearly noted in Figure 4 of the drawings. A longitudinally ex'- tending recess 24 is formed on the upper side of the casing 2| and opens at one end into the bore 22.

A transverse hinge or pivot pin 25 is fixedly secured in the casing 20 within the recess 24 remote from the bore 22. A movable contacter member 28 is mounted on the pivot pin 25 for engagement with a xed contact upon actuation or 3 inadvertent movement of the window guard frame I2.

The movable contactor member 26 includes a substantially horizontally extending arm 21 pivoted at one end on the pivot pin 25, the other end of the horizontal arm 21 extending into the upper end of the bore 22. A substantially vertically extending arm 28 is pivotally mounted by the hinge pin '29 on the end of the arm 21 within the bore 22, clearly noted in Figure 4 of the drawings, the vertically extending arm 28 depending from the lower end of the bore 22. The lower end of the depending arm 28 is formed in the manner of' an eye or hook '29 for receiving one end of the outwardly extending, transverse, upper bar 20 of the window guard frame I2. The engagement of the outwardly extending pintle members 38 on the opposite ends of the upper transverse bar v2|] through the hooks or eyes 29 substantially suspend the window guard frame I2 from the depending, vertically extending, movable contactor member 26. Y

A pair of transversely extending vertically spaced xed contacts 3| and 32 are xedly secured within the'casing-ZI adjacent the end of the horizontally extending contact arm 21 adjacent the vertically extending bore 22. The upper, iixed contact member 3l is adapted to be engaged by the upper surface of the horizontally extending arm 21 of the movable contactor 26, the fixed contact member 3| constituting an abutment member for limiting the upward swinging of the movable contactor member. The lower, xed contact member 32 is adapted to be engaged by the lower edge of the longitudinally extending arm 21 of the movable contactor member 26 for limiting the downward swinging movement of the contactor member 26, as biased downwardly by the weight of the window guard frame I2.

A central, upwardly opening recess 34 is formed in the center of the housing 2|, the upper end of the countenbore or recess 313 openingrv into the lower side of the recess 24 in which .the movable contact 26 is mounted. A spring 35 abuts at its lower end on the casing 2|, the spring 35 being engaged in the recess 34, and the upper end of the spring 35 engages the lower edge of the horizontally extending arm 21 of the movable contact member 26 for constantly biasing the movable contactor member 26 upwardly against the weight of the guard frame I2. Under normal conditions, the spring 35 will exactly ybalance the weight of the window guard frame I2 so that the horizontally extending, movable contact arm 21 will be positioned between the vertically spaced apart xed contacts 3| and 32, as clearly noted in Figure 4 ofthe drawings.

A An annular, xed contact 36 is mounted on the lower end of the bore 22, the fixed contact 36 being disposed concentric to the axis of the bore 22, whereby the depending arm 28 of the movable contact member 26 may be suspended from its pivot 23 out of engagement with theinner edge of the annular contact 36 in the normal position of the window guard frame I2.

The electric circuit I comprises a wire 31 which is connected between the fixed contacts 3 I, 32 and 36 and one side of the alarm member I6. Another Wire 38 is connected between the pivot pin 26 of the movable contactor arm 21 and one side of the battery 39, or other source of electrical power for the circuit I5. A wire 40 is connected between the other side of the battery 39 and the remaining side of the alarm member I6, a main or master switch 5I being connected in the wire 48. Where a switch I4 is used on the opposite sides of the window frame I0, a common connector member 42 is connected between the fixed contact members of the respective switches I4, so that closing of either one vof the switches I4 will complete or close the circuit to the same alarm member I6 in the manner clearly noted in Figure 1 of the drawings.

In the use and operation of the window alarm described above, the window alarm frame I2 will normally be suspended from the depending arm 28 for free swinging movement therefrom, the vertical contact arm 28 being positioned out of engagement with the annular contact 36, and the horizontally positioned, movable contactor arm 21 being normally positioned between the vertically spaced apart, xed contacts 3| and 32 in the manner clearly shown in Figure 4 of the drawings. When the window guard frame I2 is balanced by the spring 35 in intermediate position, the movable contactor member 26 is out of engagement with the fixed contacts 3|, 32 and 36, the alarm circuit I5 is in a sensitive condition, the master switch 4I being in closed position. Uponany movement of the guard frame I2, the alarm circuit I5 will be closed for actuating the alarm member I6. It will be noted that upon raising the frame I2, the movable contactor arm 21 will engage the upper, fixed contact 3| and upon downward movement of the frame I2, the movable contactor arm 21 will engage the lower, fixed Contact 32. Upon any swinging movement of the window guard frame I2, the vertically extending, movable contactor arm 28 will engage the annulariixed contact 36.

As the house wiring circuit is also a vulnerable point which is frequently broken, as by cutting or other circuit disconnecting means, by a person desiring unlawful entry to a homefor other dwelling which may be protected by electric burglar alarms, I have provided a switch 50 adapted to be connected in parallel with the alarm circuit I5 for sounding the alarm I6 upon breaking the main electric circuit 5| of the dwelling.

The switch 53 includes an armature 52 pivoted at one end on a pivot pin 54 and connected to a wire 55, which, in turn, is connected to the wire 3S of the alarm circuit I5 between the battery l39 and alarm I6. The other contact 56 of the switch 5|! is connected by the wire 51 to the wire 31 on the other side of the alarm I6 in such a manner that when the armature 52 is in engagement with the other contact 56, the alarm circuit will be closed for actuating the alarm I6 in the same manner as when the circuit is closed by the switc I4 described above.

The armature 54 will normally be biased to a switch opening position by a spring 58, by gravity or other suitable biasing means. An electromagnet 59 is connected to the main house circuit 5I at a point to be actuated at all times until the entrance or main wire connections to' the house are broken. The electromagnet 59, when actuated by the house circuit 5I will rock the armature 52 out of engagement with the contact 56 to open the switch 50 and consequently the alarm circuit I5. The electromagnet 59 operates in opposition to the spring 58, or other biasing means acting on the armature so that upon failure of the main circuit 5| the alarm circuit will be closed.

While the main power alarm switch 50 is shown in the drawings as being connected in the same alarm circuit as the window alarm switch I4, it

is to be understood that the power alarm switch may be connected on a separate alarm circuit or in combination with another alarm switch which is normally open.

I do not mean to conne myself to the exact details of construction herein disclosed, but claim all variations falling within the purview of the appended claims.

I claim:

1. In a' switch, an insulated body, a generally horizontal contactor arm pivoted at one end on said body and having a free end, a generally perpendicular contactor arm pivoted at its upper end on the free end of said horizontal contactor arm, upper and lower xed contacts on said body located above and below said horizontal contactor arm, resilient means acting between said body and said horizontal contactor arm serving to normally position said horizontal contactor arm in an intermediate position wherein said horizontal contactor arm is vertically spaced from and out of contact with said upper and lower contacts, an annular contact on said body surrounding said perpendicular contactor arm with which said perpendicular contactor arm is normally out of contact, and means electrically connecting said upper, lower, and annular contacts together.

2. In a switch, an insulated body, a generally horizontal contactor arm pivoted at one end on said body and having a free end, a generally perpendicular contactor arm pivoted at its upper end on the free end of said horizontal contactor arm, upper and lower xed contacts on said body located above and below said horizontal contactor arm, resilient means acting between said body and said horizontal contactor arm serving to normally position said horizontal contactor arm in an intermediate position wherein said horizontal contactor arm is vertically spaced from and out of contact with said upper and lower contacts,

an annular contact on said body surrounding said perpendicular contactor arm with which said perpendicular contactor arm is normally out of contact, and means electrically connecting said upper, lower, and annular contacts together, said perpendicular contactor arm having a member suspended thereon below said body, said member being arranged to be swung in different lateral directions so as to engage said perpendicular contactor arm with said annular contact or elevated or depressed to engage said horizontal contactor arm with said upper or lower contacts.

3. In combination, a support including a frame enclosing an access opening, an insulated body mounted on an upper part of said frame, said insulated body having switch means thereon including annular contact means and contactor means, said contactor means including an element depending from said body, said element being movable vertically in opposite directions and laterally to engage said annular contact means and close a circuit, and a guard frame in protective relation to said access opening and said support frame and secured to depend from said depending element, said guard frame being otherwise unsupported by said support and being free to be raised or lowered or moved laterally with respect to the support frame to operate said switch means.

JAMES W. BROOKS.

REFERENCES CITED The following references are of record 1n the flle of this patent:

UNITED STATES PATENTS Number Name Date 1,305,190 Bobo May 27, 1919 1,729,137 Stalmach Sept. 24, 1929 2,353,452 Fruh July 11, 1944 

